340 swap-small block k frame or motor mounts?
I'm in the process of re-doing the Schumacher mount deal with a 360 in a slant six car. (The previous owner did it all WRONG.) If I were to start from scratch, I'd go the K-frame swap route. With the conversion mounts, you need to trim and drill the driver's side saddle (perch). At this point you may be thinking about rebuilding the front suspension and changing torsion bars anyway, so while you've got it all apart, why not just swap K's, eh?
Just my $.02, but I think this is the "right" way to do it.